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5 Things to Remember When Contesting Field Sobriety Tests

When a driver has decided to refuse blood or Breathalyzer tests, a field sobriety test may be the main or only evidence of her intoxication.

Although there are often penalties to refusing chemical tests for alcohol, it can be a lot easier to beat a DUI case with only a field sobriety test as evidence.

Here are five things to remember when contesting a field sobriety test (FST) in court:

1. If You Refuse Blood Test or Breathalyzer, You Will Lose Your License.

Even if you are later aquitted of your DUI/DWI charge, under Illinois law your license will be automatically suspended for a year.

2. Field Sobriety Tests Aren't Always Reliable.

Taken as a whole, the standard FST accurately indicates alcohol impairment in 91% of cases, but that leaves 9% of cases in which a person with a legal blood alcohol content (BAC) could fail.

3. Challenge the Execution of the Test.

The National Highway Traffic Safety Administration (NHTSA) acknowledges three standard methods for conducting a FST:

  • Horizontal gaze nystagmus (HGN). This test tracks the involuntary jerking of your eyes and inability to follow objects from left to right.
  • Walk and turn (WAT). This is a balance and coordination test requiring nine heel-to-toe steps forward and then back.
  • One-Leg Stand (OLS). Another balancing test, this requires you to stand on one leg for a period of time.

If these tests are not performed in accordance with the NHTSA guidelines, the test can be challenged as not reliable.

4. Common Medical Conditions.

If you failed the FST, you can challenge the results if you have a medical or physical condition that would skew the results, such as:

  • An inner ear infection/condition. The center of your balance and equilibrium, when injured, can cause imbalance.
  • Nerve or brain injury. Neurological damage can cause jerkiness in the eyes and make a HGN test unreliable.
  • Issues walking/standing. Club feet or any number of skeletal or muscular issues can cause sober persons to fail the FST.

5. Preliminary Breath Screening Device.

A driver is allowed to refuse a preliminary breath screening device, but this device is not reliable in court to prove intoxication.

On the other hand, if the screening device indicates that there was no alcohol detected, a defendant can use this as evidence of his sobriety.

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